Any enthusiastic app fan can be an instant expert

There's always something gratifying about making an observation about life, the universe and everything, only to see it confirmed in newsprint with figures to back it up.

This week's "I knew it!" moment came when an unexpected traffic jam saw my husband use the TomTom app on his iPhone to navigate us away from snarled-up streets. "I bet no-one buys actual satnavs anymore," I said idly, prodding the screen while the Yoda voice-over told us to go left, but not to the dark side.

Lo and behold, a few days later, a news article confirmed it: TomTom suffered a 19 per cent decline in sales in the third quarter of this year. Garmin, another satnav-peddler, had also seen its sales go into reverse.

Dashboard-mounted traffic-scrying devices aren't the only items to have seen their virtual counterpoints overtake on the inside, of course. Later the same day, listening to my stepdaughter delight us for quite some time with her viola practice, I stumbled on an app she'd downloaded that told you if you were playing in tune or not. Hers was the Cleartune chromatic tuner, and cost a couple of quid, but a bit of Googling revealed around 20 more.

Now, I'm guessing that concert viola players (violalists? Violicians?) probably prefer a dedicated gadget, but for the average amateur, keen to improve but not fussed about professional-grade equipment, an app that's always in your pocket and doesn't cost much is preferable. If you have a smartphone and a yearning to improve your piano playing, say, why would you buy a standalone metronome when you can download a virtual version for free?

The same goes for all sorts of kit – photographic light meters can be had for pence; a shed's-worth of tools can be loaded onto your handset (cyber calipers, anyone?) and the iThermometer (69p) promises to take your temperarure on the go.

What I'd like to see now, though, is a nice fact-tastic news report that supports my theory that for every starving metronome maker or light-meter manufacturer, there's a fair-weather pianist who never would have bought a piece of specialist equipment but is happy to have discovered a cheap and cheerful app that does the business.

The tools of experts are now in the hands of enthusiastic amateurs. It's nice and democratic, right? And we're all learning new things. It would certainly make me feel much better about the fate of the hungry metronome elves. And I sense that GPs needn't worry too much about being out of the temperature-taking game – the iThermometer's single-star score makes me think that app fans are a rather sensible bunch.